Ventilator with switching valve

ABSTRACT

Disclosed is a ventilator with an apparatus input and an apparatus output and with an airway between the apparatus input and the apparatus output. A breathing gas drive, a non-return valve and a switching valve are arranged in the airway. The non-return valve prevents a flow of breathing gas in a direction from the apparatus output to the apparatus input and the switching valve enables at least temporarily a flow of breathing gas in a direction from the apparatus output to the apparatus input.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. § 119 of GermanPatent Application No. 102018001888.2 filed Mar. 8, 2018, the entiredisclosure of which is expressly incorporated by reference herein.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a ventilator with an apparatus inputand an apparatus output and with an airway between the apparatus inputand the apparatus output, wherein a breathing gas drive, a non-returnvalve and a switching valve are arranged in the airway.

2. Discussion of Background Information

Ventilators are used for the therapy of respiratory disorders, and thusthe ventilators can be used in non-invasive and invasive ventilation,both in and out of hospitals.

For the artificial respiration of patients, a ventilator can as a rulebe used which has an inspiratory branch for the breathing gas flow andoptionally a branch for the expiratory gas flow. The branch for theexpiratory breathing gas flow enables the exhalation/expiration of abreathing gas through the patient, whilst the branch for the inspiratorygas flow provides the patient with the breathing gas.

With the ventilators known from the prior art there may arise bothblockages/obstructions in the expiratory branch and also in theinspiratory branch of the ventilator.

A blockage/obstruction in the expiratory branch can be caused by way ofexample by the intake of material, such as by way of example medicamentsor secretions.

Blockages/obstructions in the expiratory branch can prevent a patientfrom exhaling breathing gas.

A blockage/obstruction of the expiratory branch can lead by way ofexample to the airway pressure in the expiration not being able to dropto the intended pressure level, whereby a patient cannot breathe out. Astalling increased airway pressure in the airways of the patient canhave harmful consequences. It can lead by way of example to a dangerousrise in the intrathoracic pressure, which leads to a reduced venousreturn, reduced cardiac output and finally to a drop in the arterialblood pressure.

In addition to the problems of a blockage/obstruction in the expiratorybranch of the ventilator, there may also be a blockage/obstruction inthe inspiratory branch of the ventilator. A blockage/obstruction in theinspiratory branch can be caused by way of example by a malfunction ofthe breathing gas drive. Blockages/obstructions in the inspiratorybranch can prevent or at least impede the patients from breathing in.

The ventilators known from the prior art thus have the disadvantagethat, even with existing safety devices, they are not sufficientlysafeguarded against blockages, obstructions or malfunctions, so thatinspiration and/or expiration of the breathing gas cannot be guaranteed.

In view of the foregoing it would be advantageous to have available aventilator which ensures security of inspiration and/or expiration ofbreathing gas in the event of an obstruction/blockage of an inspiratoryor expiratory branch of the ventilator.

SUMMARY OF THE INVENTION

The present invention provides a ventilator with at least one apparatusinput and one apparatus output and with an airway between the apparatusinput and apparatus output, wherein a breathing gas drive, a non-returnvalve and a switching valve are arranged in the airway. The airwayusually is an inspiratory airway. The ventilator can optionally compriseat least one inspiratory airway and at least one expiratory airway. Moretypically, at least one non-return valve is arranged in at least oneinspiratory airway. The non-return valve can be arranged between theapparatus input and the breathing gas drive. The non-return valve canalternatively be arranged between the breathing gas drive and theapparatus output. A breathing gas drive can be a blower or a pressuresource, more particularly an oxygen or air pressure source.

According to the invention the non-return valve prevents a flow ofbreathing gas in a direction from the apparatus output to the apparatusinput, and the switching valve enables at least temporarily a flow ofbreathing gas in the direction from the apparatus output to theapparatus input or to a separate apparatus opening. The separateapparatus opening can be here a second/separate apparatus input or asecond/separate apparatus output. A switching valve can beelectromechanical in design. A switching valve can be by way of examplea pneumatic valve with a magnetic valve, or a bypass with a magneticvalve. A switching valve can be a 3/2-way valve, a pneumatic valve or adiaphragm valve.

As a rule, expirated breathing gas from the patent can be discharged viaan expiratory airway of the ventilator. A return of the breathing gasthrough the inspiratory airway can thus be prevented. The non-returnvalve prevents undesired contamination of the breathing gas drive fromthe non-purified breathing gas of the patient during normal operation ofthe ventilator. In the event of a blockage/obstruction of the expiratoryairway the non-return valve can be reversed at least temporarily by theincorporated switching valve. This has the advantage that, in the eventof a blockage of the expiratory airway, the breathing gas of the patientcan be discharged via the inspiratory airway.

In one configuration a flowmeter is arranged between the non-returnvalve and the apparatus output. The flowmeter is set up to detect a flowor volume or a pressure of the breathing gas in the airway. Theswitching valve is set up so that it can be opened or closed based onthe detected flow or volume or pressure of the breathing gas. Thisenables the switching valve to be switched in dependence on the volumeor pressure of the breathing gas. Alternatively, the switching valve canbe time-controlled or patient-triggered. The switching valve can beswitched by way of example by a 3/2-way valve.

In another configuration the switching valve is arranged in a bypassaround the non-return valve. The bypass can be designed open or closed.Closed means that the bypass opens into the airway from which it isbranched off and then bypasses the non-return valve. The switching valveis as a rule arranged in the bypass. Open means that the bypass does notopen into the airway from which it branches off. Rather an open bypassis an airway which can have by way of example a separate/secondapparatus output. The open bypass as a rule branches off between theapparatus output and the breathing gas drive or the non-return valve,and opens in the separate/second apparatus output. Alternatively, theopen bypass can branch off between the non-return valve and thebreathing gas drive, and open into the second/separate apparatus output.A flowmeter can be arranged in the open bypass. The flowmeter is usuallyarranged between the second/separate apparatus output and the bypass. Aseparate switching valve can be arranged in the open bypass. Theswitching valve can be switched time-controlled, patient-triggered orbased on a flow or volume or pressure of the breathing gas detected bythe flowmeter. The flowmeter is as a rule arranged between the switchingvalve and the common apparatus output. The open bypass can optionally beformed additionally to a closed bypass. The open bypass has theadvantage that breathing gas exhaled by the patient can be discharged tothe atmosphere via the separate/second apparatus output.

In a further design of the invention the at least one switching valveforms a bypass around the non-return valve. By designing the closedbypass around the non-return valve, it is possible to bypass thenon-return valve in such a way that the breathing gas is introducedround the non-return valve into the same airway from which it wasbranched off. The at least one switching valve optionally forms an openbypass around the non-return valve. In the case of the open-type bypass,breathing gas can, in the event of a blockage/obstruction of theinspiratory airway, be discharged via the open bypass past thenon-return valve through a separate apparatus output.

In one configuration the at least one switching valve is set up to openand/or close the bypass, wherein the switching valve is set up so thatit can be switched automatically or actively. Usually, the switchingvalve is set up to open or close automatically, based on the detectedflow or volume or pressure of the breathing gas. By way of example theswitching valve opens when the flowmeter detects a higher pressure overa certain period of time.

In another configuration the breathing gas drive is arranged between theapparatus input and the non-return valve and is set up to conveybreathing gas in the direction of the non-return valve and the apparatusoutput. The arrangement of the breathing gas drive defines a suctionside and a pressure side in the ventilator. The suction side is the sidein the gas flow direction upstream of the breathing gas drive. Thepressure side is the side downstream of the breathing gas drive in thegas flow direction. By arranging the breathing gas drive directly behindthe apparatus input, the non-return valve, the switching valve and theflow meter are located on the pressure side of the ventilator.

In one configuration according to the invention, the bypass branches offto the switching valve between the breathing gas drive and thenon-return valve and opens back again into the airway between thenon-return valve and the apparatus output. Through this arrangement, thebreathing gas drive is protected during normal operation of theventilator against undesired contamination through returning breathinggas.

In an alternative configuration of the invention the breathing gas driveis arranged between the non-return valve and the apparatus output and isset up to convey breathing gas towards the apparatus output. Byarranging the breathing gas drive between the non-return valve and theapparatus output, the non-return valve and the switching valve arelocated on the suction side of the ventilator.

In a further development of the alternative configuration of theinvention the bypass branches off to the switching valve between theapparatus input and the non-return valve, and opens back again into theairway between the non-return valve and the breathing gas drive. Thishas the advantage that the non-return valve can be bypassed. With anarrangement of this kind the switching valve and the non-return valveare moreover arranged on the suction side of the ventilator.

In a further configuration, in addition to the bypass, a second airwayis formed which comprises a second apparatus input and at least onenon-return valve, and opens in front of the common apparatus output intothe first airway. More typically, the second airway is a separateinspiratory airway which is set up to provide, in the event of ablockage/obstruction of the inspiratory airway, a separate airway viawhich breathing gas can be inspirated. The second inspiratory airway cancomprise a separate breathing gas drive. By way of example the breathinggas drive is arranged between the second apparatus input and thenon-return valve of the second airway. Furthermore, the second airwaycan comprise a separate flowmeter which is set up to detect the flow orvolume or pressure of the breathing gas in the second airway.

In a further configuration according to the invention, an airway isincluded for an expiratory gas flow which comprises an expiratoryapparatus input and an expiratory apparatus output.

The airway for an expiratory gas flow is set up to discharge thebreathing gas of the patient. The expiratory apparatus input is thenarranged as a rule close to the patient whilst the expiratory apparatusoutput is formed away from the patient. The airway for the expiratorygas is set up to discharge the breathing gas of the patient at theexpiratory apparatus output and thus to enable the patient to breatheout.

In a further development the airway leads from the expiratory apparatusinput to the expiratory apparatus output, and a switching valve and aflowmeter are arranged in the airway. The flowmeter is arranged as arule between the expiratory apparatus output and the switching valve.The switching valve is as a rule set up so that it can be switched basedon a fixed time interval or by patient trigger. Alternatively, theswitching valve can be switched based on the flow or volume or pressureof the breathing gas as measured by the flowmeter. The flowmeter whichis arranged between the expiratory apparatus output and the switchingvalve is typically set up to detect the flow or volume or the pressureof the breathing gas and to enable feedback at the ventilator about thebreathing gas discharged by the patient.

In a further development a separate expiratory airway with a switchingvalve and a flowmeter runs between the expiratory apparatus input andthe switching valve to a separate apparatus output. The separateexpiratory airway is set up to discharge the breathing gas of thepatient, by way of example in the event of a blockage/obstruction of theexpiratory airway. The flowmeter which is arranged between theexpiratory apparatus output and the switching valve is typically set upto detect the flow or volume or the pressure of the breathing gas and toenable feedback about the breathing gas which is discharged by thepatient.

In one configuration a tube system is adapted to the apparatus outputand leads with a first branch to a patient interface and, in front ofthe patient interface, with a second branch to the expiratory apparatusinput for expiratory breathing gas. The tube system is optionally asingle-tube system. Alternatively, a tube system can be adapted to theapparatus output in the form of a leakage tube system. The patientinterface is connected by the tube system to at least one inspiratoryairway. The patient interface is optionally connected by the tube systemto at least one inspiratory airway and at least one expiratory airway.

In a further configuration the non-return valve prevents the flow ofbreathing gas in a direction from the apparatus output to the apparatusinput, and the switching valve enables at least temporarily a flow ofbreathing gas in a direction from the apparatus output to the apparatusinput, wherein the switching valve is arranged in a bypass around thenon-return valve, wherein the bypass branches off to the switching valvebetween the breathing gas drive and the non-return valve, and opens backagain into the airway between the non-return valve and the apparatusoutput.

In a further development of the invention the ventilator comprises asecond inspiratory airway, which comprises a separate apparatus inputand a further non-return valve, wherein the second inspiratory airway isset up to draw in a breathing gas through the separate apparatus inputand convey it towards the apparatus output.

In a further development, the switching valve is arranged in the bypass,wherein the bypass is formed as an open bypass which comprises aseparate apparatus output, wherein the open bypass branches off from theinspiratory airway between the non-return valve and the apparatusoutput, and opens into the separate apparatus output.

In a further development of the invention the switching valve isarranged in the bypass, wherein the bypass is formed as an open bypasswhich comprises a separate apparatus output, wherein the open bypassbranches off from the inspiratory airway between the non-return valveand the apparatus output, and opens into the separate apparatus output,wherein the inspiratory airway comprises at least one further valve.

In another further development, the switching valve is arranged in thebypass, wherein the bypass is formed as an open bypass which comprises aseparate apparatus output, wherein the open bypass branches off from theinspiratory airway between the non-return valve and the apparatusoutput, and opens in the separate apparatus output, wherein at least oneflowmeter is arranged in the open bypass.

The present invention further provides a ventilator with at least oneapparatus input and one apparatus output and with an airway between theapparatus input and apparatus output, wherein a breathing gas drive, anon-return valve and a switching valve are arranged in the airway. Theventilator comprises a second inspiratory airway which comprises aseparate apparatus input and a further non-return valve, wherein thesecond inspiratory airway is set up to draw breathing gas in through theseparate apparatus input and convey it towards the apparatus output.

The present invention further provides a ventilator with at least oneapparatus input and an apparatus output and with an airway between theapparatus input and apparatus output, wherein a breathing gas drive, anon-return valve and a switching valve are arranged in the airway. Theswitching valve is arranged in a bypass, wherein the bypass is designedas an open bypass which comprises a separate apparatus output, whereinthe open bypass branches off from the inspiratory airway between thenon-return valve and the apparatus output, and opens into the separateapparatus output.

In one configuration the switching valve is arranged in the bypasswherein the bypass is designed as an open bypass which comprises aseparate apparatus output, wherein the open bypass branches off from theinspiratory airway between the non-return valve and the apparatus outputand opens into the separate apparatus output, wherein the inspiratoryairway comprises at least one further valve.

In a further configuration the switching valve is arranged in thebypass, wherein the bypass is designed as an open bypass which comprisesa separate apparatus output, wherein the open bypass branches off fromthe inspiratory airway between the non-return valve and the apparatusoutput, and opens in the separate apparatus output, wherein at least oneflowmeter is arranged in the open bypass.

The present invention further provides a ventilator with at least oneapparatus input and an apparatus output and with an airway between theapparatus input and the apparatus output, wherein a breathing gas drive,a non-return valve and a switching valve are arranged in the airway. Theswitching valve is arranged in a bypass, wherein the bypass is designedas an open bypass, which comprises a separate apparatus output, whereinthe open bypass branches off from the inspiratory airway between thenon-return valve and the apparatus output, and opens in the separateapparatus output, wherein the inspiratory airway comprises at least onefurther valve and a flowmeter, wherein the flowmeter is arranged betweenthe breathing gas drive and the non-return valve.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred exemplary embodiments of the invention will now be explainedbelow in further detail with reference to severely simplifieddiagrammatic illustrations. In the drawings:

FIG. 1 shows a diagrammatic structure of an embodiment of a ventilatoraccording to the invention with an inspiratory airway with a bypassaround a non-return valve;

FIG. 2 shows an alternative arrangement of the embodiment of theventilator according to the invention shown in FIG. 1, with theinspiratory airway with the bypass around a non-return valve;

FIG. 3 shows a diagrammatic structure of a further embodiment of theventilator according to the invention shown in FIG. 1, with theinspiratory airway with the bypass and a second inspiratory airway;

FIG. 4 shows an alternative arrangement of the embodiment, shown in FIG.2, of the ventilator according to the invention shown in FIG. 1, withthe inspiratory airway with the bypass and the second inspiratoryairway;

FIG. 5 shows an alternative arrangement of the embodiment, shown in FIG.1 and FIG. 3, of the ventilator according to the invention, with theinspiratory airway with the bypass and the second inspiratory airway;

FIG. 6 shows an alternative arrangement of the embodiment, shown in FIG.2 and FIG. 4, of the ventilator according to the invention, with theinspiratory airway with the bypass and the second inspiratory airway;

FIG. 7 shows a diagrammatic structure of an embodiment of the ventilatoraccording to the invention with the inspiratory airway with the bypassand the expiratory airway;

FIG. 8 shows a diagrammatic structure of a further embodiment of theventilator according to the invention with the inspiratory airway andthe second inspiratory airway as well as with an expiratory airway and aseparate expiratory airway;

FIG. 9 shows a diagrammatic structure of an alternative embodiment ofthe ventilator according to the invention with the inspiratory airwaywith an open bypass with a separate apparatus output;

FIG. 10 shows a diagrammatic structure of an alternative embodiment ofthe ventilator according to the invention, shown in FIG. 9, with theinspiratory airway with the open bypass with the separate apparatusoutput;

FIG. 11 shows a diagrammatic structure of an alternative embodiment ofthe ventilator according to the invention, shown in FIG. 9, with theinspiratory airway with the open bypass with the separate apparatusoutput;

FIG. 12 shows a diagrammatic structure of an alternative embodiment ofthe ventilator according to the invention—shown in FIGS. 9 and 11—withthe inspiratory airway with an open bypass with a separate apparatusoutput.

In the figures the same structural elements are each provided with thesame reference numerals.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The particulars shown herein are by way of example and for purposes ofillustrative discussion of the embodiments of the present invention onlyand are presented in the cause of providing what is believed to be themost useful and readily understood description of the principles andconceptual aspects of the present invention. In this regard, no attemptis made to show details of the present invention in more detail than isnecessary for the fundamental understanding of the present invention,the description in combination with the drawings making apparent tothose of skill in the art how the several forms of the present inventionmay be embodied in practice.

FIG. 1 shows a diagrammatic structure of an embodiment of a ventilator10 according to the invention with an inspiratory airway 16 a with abypass 17 and the non-return valve 13 a. The inspiratory airway 16 acomprises an apparatus input 11 a and an apparatus output 15 a. Theapparatus output 15 a is arranged here close to the patient and theapparatus input 11 a is arranged away from the patient. The airway 16 aextends from the apparatus input 11 a to the apparatus output 15 a. Theairway 16 a comprises a breathing gas drive 12 a, a non-return valve 13a and a switching valve 14 a. The switching valve 14 a is arranged in abypass 17 around the non-return valve 13 a. The bypass 17 branches offbetween the breathing gas drive 12 a and the non-return valve 13 a andopens back into the inspiratory airway 16 a between the non-return valve13 a and the apparatus output 15 a. The breathing gas drive 12 a isarranged between the apparatus input 11 a and the non-return valve 13 a.Breathing gas can be returned in the direction of the apparatus input 11a via the switching valve 14 a arranged in the bypass 17, whereby thenon-return valve 13 a is bypassed.

FIG. 2 shows an alternative arrangement of the embodiment of theventilator 10 according to the invention shown in FIG. 1, with theinspiratory airway 16 a with the bypass 17 around the non-return valve13 a. The inspiratory airway 16 a comprises the apparatus input 11 a andthe apparatus output 15 a. The airway 16 a extends from the apparatusinput 11 a to the apparatus output 15 a. The airway 16 a comprises thenon-return valve 13 a, the breathing gas drive 12 a and the switchingvalve 14 a. The switching valve 14 a is arranged in the bypass 17 aroundthe non-return valve 13 a. The bypass 17 in this alternative arrangementbranches off between the apparatus input 11 a and the non-return valve13 a, and opens back again into the inspiratory airway 16 a between thenon-return valve 13 a and the breathing gas drive 12 a. The breathinggas drive 12 a is arranged between the non-return valve 13 a and theapparatus output 15 a. After it has passed the breathing gas drive 12 athe breathing gas can be returned in the direction of the apparatusinput 11 a via the switching valve 14 a which is arranged in the bypass17.

FIG. 3 shows a diagrammatic structure of a further embodiment of theventilator 10 according to the invention, shown in FIG. 1, with theinspiratory airway 16 a, the bypass 17 and a second inspiratory airway16 b. The inspiratory airway 16 a extends from the apparatus input 11 ato the apparatus output 15 a. The inspiratory airway 16 a comprises thebreathing gas drive 12 a, the non-return valve 14 a and the switchingvalve 14 a, wherein the switching valve 14 a is arranged in the bypass17 to bypass the non-return valve 13 a. The embodiment of the ventilator10 shown in FIG. 3 has a second inspiratory airway 16 b which extendsfrom a second apparatus input 11 b to the common apparatus output 15 a.The second inspiratory airway 16 b opens into the inspiratory airway 16a between the non-return valve 13 a and the common apparatus output 15a. The second inspiratory airway 16 b can comprise a non-return valve 13b. In the event of a blockage/obstruction of the inspiratory airway 16 aby way of example, breathing gas can be drawn in through the secondinspiratory airway 16 b via the separate apparatus input 11 b andsupplied to the patient. In addition, in the event of a blockage of anexpiratory airway, breathing gas can be returned through the switchingvalve 14 a whilst bypassing the non-return valve 13 a, thereby enablingthe patient to breathe out.

FIG. 4 shows an alternative arrangement of the embodiment, shown in FIG.2, of the ventilator 10 according to the invention, with the inspiratoryairway 16 a, the bypass 17 and the second inspiratory airway 16 b. Withthis alternative embodiment the non-return valve 13 a is arranged in theinspiratory airway 16 a between the apparatus input 11 a and thebreathing gas drive 12 a. The bypass 17, which is formed around thenon-return valve 13 a, branches off between the apparatus input 11 a andthe non-return valve 13 a and opens back into the inspiratory airway 16a between the non-return valve 13 a and the breathing gas drive 12 a.The breathing gas drive 12 a is arranged between the non-return valve 13a and the apparatus output 15 a. The second inspiratory airway 16 bopens into the inspiratory airway 16 a between the breathing gas drive12 a and the common apparatus output 15 a. The second inspiratory airway16 b can comprise a non-return valve 13 b. Also with this embodiment, byway of example in the event of a blockage/obstruction of the inspiratoryairway 16 a, breathing gas can be drawn in through the secondinspiratory airway 16 b via the separate apparatus input 11 b andsupplied to the patient. In addition, likewise in the event of ablockage of an expiratory airway, breathing gas can be returned throughthe switching valve 14 a by bypassing the non-return valve 13 a, therebyenabling the patient to breathe out.

FIG. 5 shows an alternative arrangement of the embodiment, shown inFIGS. 1 and 3, of the ventilator 10 according to the invention, with theinspiratory airway 16 a, the bypass 17 and the second inspiratory airway16 b.

The inspiratory airway 16 a extends from the apparatus input 11 a to theapparatus output 15 a and comprises the breathing gas drive 12 a, thenon-return valve 14 a and the switching valve 14 a. The switching valve14 a is arranged in the bypass 17 around the non-return valve 13 a. Thebypass 17 is formed between the breathing gas drive 12 a and theapparatus output 15 a. The embodiment of the ventilator 10 shown in FIG.5 likewise has the second inspiratory airway 16 b which extends from thesecond apparatus input 11 b to the common apparatus output 15 a. Thesecond inspiratory airway 16 b opens into the inspiratory airway 16 abetween the non-return valve 13 b and the common apparatus output 15 a.The second inspiratory airway 16 b comprises a non-return valve 13 b anda breathing gas drive 12 b, wherein the breathing gas drive 12 b isarranged between the second apparatus input 11 b and the non-returnvalve 13 b. Also with this embodiment, by way of example in the event ofa blockage/obstruction of the inspiratory airway 16 a, breathing gas canbe drawn in through the second inspiratory airway 16 b via the separateapparatus input 11 b and supplied to the patient. In addition, likewisein the event of a blockage of an expiratory airway, breathing gas can bereturned through the switching valve 14 a arranged in the bypass 17 soas to bypass the non-return valve 13 a and enable the patient to breatheout.

FIG. 6 shows an alternative arrangement of the embodiment of theventilator 10 according to the invention shown in FIG. 2 and FIG. 4,with the inspiratory airway 16 a, the bypass 17 and the secondinspiratory airway 16 b. The inspiratory airway 16 a extends from theapparatus input 11 a to the apparatus output 15 a and comprises thenon-return valve 13 a, the switching valve 14 a and the breathing gasdrive 12 a. The switching valve 14 a is arranged in the bypass 17 tobypass the non-return valve 13 b. The bypass 17 with the switching valve14 a is arranged between the apparatus input 11 a and the breathing gasdrive 12 a. The embodiment of the ventilator 10 shown in FIG. 6 has thesecond inspiratory airway 16 b which extends from a second apparatusinput 11 b to the common apparatus output 15 a. The second inspiratoryairway 16 b opens into the inspiratory airway 16 a between the breathinggas drive 12 a and the common apparatus output 15 a. The secondinspiratory airway 16 b comprises the non-return valve 13 b and abreathing gas drive 12 b, wherein the breathing gas drive 12 b isarranged between the second apparatus input 11 b and the non-returnvalve 13 b.

FIG. 7 shows a diagrammatic structure of an embodiment of the ventilator10 according to the invention with the inspiratory airway 16 a with abypass 17 and an expiratory airway 16 c.

The inspiratory airway 16 a extends from the apparatus input 11 atowards the apparatus output 15 a. The inspiratory airway 16 a compriseshere the breathing gas drive 12 a, as well as the non-return valve 13 aand the switching valve 14 a, which is arranged in a bypass 17 aroundthe non-return valve 13 a, as well as a flowmeter 18 a. The flowmeter 18a is arranged between the bypass 17 and the apparatus output 15 a. Aflow or volume or pressure of the breathing gas in the airway can bedetected via the flowmeter 18 a. With a predetermined volume or pressureof breathing gas over a predetermined period of time, the switchingvalve can be switched by way of example by means of a 3/2-way valve. Theswitching valve is as a rule set up and designed to set a PEEP (positiveend-expiratory pressure) in the region of 0-20 hPa, preferably 0-15 hPa.

The expiratory airway 16 c extends from an expiratory apparatus input 21to the expiratory apparatus output 22 a and comprises a switching valve14 b and a flowmeter 18 c. The flowmeter 18 c is then arranged betweenthe expiratory apparatus output 22 a and the switching valve 14 b. Theflowmeter 18 c then serves to detect a flow or volume or a pressure ofthe breathing gas in the airway. Feedback on the volume of the breathinggas discharged by the patient can then be provided on the ventilatorbased on the values detected by the flowmeter 18 c.

A tube system 19 comprising a first branch 24 and a second branch 25 isadapted to the apparatus output 15 a. The first branch 24 leads from theapparatus output 15 a to a patient interface 20. Before the patientinterface 20 the tube system 19 leads with a second branch 25 to theexpiratory apparatus input 21 for expiratory breathing gas. A patientinterface 20 is connected via the tube system 19 to the inspiratorybranch 16 a and the expiratory branch 16 c.

With the embodiment of the ventilator 10 illustrated in FIG. 7,breathing gas can be drawn in via the apparatus input 11 a and guidedvia the breathing gas drive 12 a via the non-return valve 13 a in thedirection of the apparatus output 15 a. The breathing gas is passedfurther from the apparatus output 15 a via the branch 24 of the adaptedtube system 19 to the patient interface 20 via which a patient canbreathe in the breathing gas. The exhaled air of the patient can besupplied to the airway 16 c via the branch 25 of the adapted tube system19 via the expiratory apparatus input 21. The breathing gas is guidedvia the expiratory airway 16 c to the expiratory apparatus output 22 aand discharged into the atmosphere. In the event of ablockage/obstruction of the expiratory airway 16 c the breathing gas canbe discharged in the inspiratory airway 16 a by opening the switchingvalve 14 a in the bypass 17.

FIG. 8 shows a diagrammatic structure of a further embodiment of theventilator 10 according to the invention with the first inspiratoryairway 16 a and the second inspiratory airway 16 b, as well as with theexpiratory airway 16 c and a separate expiratory airway 16 d.

The inspiratory airway 16 a extends from the apparatus input 11 atowards the apparatus output 15 a. The inspiratory airway 16 a comprisesthe breathing gas drive 12 a, the non-return valve 13 a as well as aflowmeter 18 a. The flowmeter 18 a is arranged between the non-returnvalve 13 a and the apparatus output 15 a. The flowmeter 18 a detects aflow or a volume or a pressure of the breathing gas which is dischargedvia the inspiratory airway 16 a to the patient.

The embodiment of the ventilator 10 shown in FIG. 8 comprises a secondinspiratory airway 16 b which extends from the second apparatus input 11b to the common apparatus output 15 a. The second inspiratory airway 16b opens into the inspiratory airway 16 a between the flowmeter and thecommon apparatus output 15 a. The second inspiratory airway 16 b cancomprise the separate breathing gas drive 12 b, the non-return valve 13b and a flowmeter 18 b.

The separate breathing gas drive 12 b is arranged between the secondapparatus input 11 b and the non-return valve 13 b. The flowmeter 18 bcan detect a volume or pressure of the inspiratory breathing gas in theairway 16 b and send it to the ventilator 10. In the event of a blockageof the inspiratory airway 16 a breathing gas can be drawn in via thesecond inspiratory airway 16 b through the apparatus input 11 b andsupplied to the patient.

The embodiment of the ventilator 10 shown in FIG. 8 further comprisesthe expiratory airway 16 c which extends from the expiratory apparatusinput 21 to the expiratory apparatus output 22 a and comprises theswitching valve 14 b and the flowmeter 18 c. The flowmeter 18 c isarranged between the expiratory apparatus output 22 a and the switchingvalve 14 b. The flowmeter 18 c detects a volume and/or a pressure of thebreathing gas which the patient is discharging. Breathing gas dischargedby the patient can be removed via the expiratory airway 16 c.

The flowmeters 18 a, 18 b, 18 c and 18 d can be set up to detect a flowor volume or a pressure of the breathing gas in the airway and to switchor open and close a switching valve based on this result or to supplyfeedback to the ventilator 10 about the flow or volume or the pressureof the breathing gas supplied to the patient or of the breathing gasdischarged by the patient.

The embodiment of the ventilator 10 shown in FIG. 8 furthermorecomprises a separate expiratory airway 16 d. The separate expiratoryairway 16 d branches off from the expiratory airway 16 c and extendstowards a separate apparatus output 22 b. The separate expiratory airway16 d comprises a switching valve 14 c and a flowmeter 18 d. Theflowmeter 18 d detects a flow or volume or a pressure of the breathinggas which the patient is discharging. In the event of ablockage/obstruction of the expiratory airway 16 c breathing gasdischarged by the patient can be discharged through the separateexpiratory airway 16 d.

A tube system 19 with a first branch 24 and a second branch 25 isadapted to the apparatus output 15 a. The first branch 24 leads from theapparatus output 15 a to a patient interface 20. Before the patientinterface 20 the tube system 19 leads with the second branch 25 to theexpiratory apparatus input 21 for expiratory breathing gas. The patientinterface 20 is connected via the tube system 19 to the inspiratoryairway 16 a, the second inspiratory airway 16 b, the expiratory airway16 c and the separate expiratory airway 16 d.

FIG. 9 shows a diagrammatic structure of an alternative embodiment ofthe ventilator 10 according to the invention with the inspiratory airway16 a with an open bypass 17 with a separate apparatus output 15 b. Theinspiratory airway 16 a of the ventilator 10 comprises the apparatusinput 11 a and the apparatus output 15 a. The breathing gas drive 12 a,the non-return valve 13 a and the switching valve 14 a are arrangedbetween the apparatus input 11 a and the apparatus output 15 a, whereinthe switching valve 14 a is arranged in the bypass 17. The bypass 17 isdesigned as an open bypass which comprises a separate apparatus output15 b. The open bypass 17 branches off from the inspiratory airway 16 abetween the non-return valve 13 a and the apparatus output 15 a, andopens in the separate apparatus output 15 b. The breathing gas drive 12a is arranged between the apparatus input 11 and the non-return valve 13a. The switching valve 14 a can be switched time-controlled,patient-triggered or based on a flow or volume of the breathing gasdetected by a flowmeter. The flowmeter is arranged here between theseparate apparatus output 15 b and the switching valve 14 a. In theevent of a blockage of the inspiratory airway 16 a, it is possible todischarge the breathing gas, discharged by the patient, through theswitching valve 14 a arranged in the open bypass 17, via the switchingvalve 14 a. Through the arrangement of the non-return valve 13 a betweenthe breathing gas drive 12 a and the apparatus output 15 a, thenon-return valve 13 a is arranged on the pressure side of the ventilator10.

FIG. 10 shows an alternative diagrammatic structure of an embodiment,shown in FIG. 9, of the ventilator 10 according to the invention withthe inspiratory airway 16 a and the open bypass 17 with the separateapparatus output 15 b. The inspiratory airway 16 a of the ventilator 10then comprises the apparatus input 11 a and the apparatus output 15 a.The non-return valve 13 a, the breathing gas drive 12 a and theswitching valve 14 a are arranged between the apparatus input 11 a andthe apparatus output 15 a, wherein the switching valve 14 a is arrangedin the bypass 17. The bypass 17 is formed as an open bypass whichcomprises a separate apparatus output 15 b. The open bypass 17 branchesoff from the inspiratory airway 16 a between the breathing gas drive 12a and the apparatus output 15 a and opens in the separate apparatusoutput 15 b. The breathing gas drive 12 a is arranged between thenon-return valve 13 a and the apparatus output 15 a. It is possible inthe event of a blockage of the inspiratory airway 16 a to dischargebreathing gas discharged from the patient via the switching valve 14 athrough the switching valve 14 a arranged in the open bypass 17. As aresult of the open bypass 17 arranged between the breathing gas drive 12a and the apparatus output 15 a, breathing gas can be returned withouthaving to pass the breathing gas drive. As a result of arranging thenon-return valve 13 a between the apparatus input 11 a and the breathinggas drive 12 a, the non-return valve 13 a is arranged on the suctionside of the ventilator 10.

FIG. 11 shows an alternative diagrammatic structure of an alternativeembodiment, shown in FIGS. 9 and 10, of the ventilator 10 according tothe invention with the inspiratory airway 16 a and the open bypass 17with the separate apparatus output 15 b. The inspiratory airway 16 a ofthe ventilator 10 comprises here the apparatus input 11 a and theapparatus output 15 a. The breathing gas drive 12 a, the non-returnvalve 13 as well as the switching valve 14 a are arranged between theapparatus input 11 a and the apparatus output 15 a, wherein theswitching valve 14 a is arranged in the bypass 17. The bypass 17 isdesigned as an open bypass which comprises a separate apparatus output15 b. The open bypass 17 branches off from the inspiratory airway 16 abetween the non-return valve 13 a and the breathing gas drive 12 a andopens in the separate apparatus output 15 b. The breathing gas drive 12a is arranged between the non-return valve 13 a and the apparatus output15 a. Through the switching valve 14 a arranged in the open bypass 17 itis possible, in the event of a blockage in the inspiratory airway 16 a,to discharge breathing gas discharged by the patient via the switchingvalve 14 a. By arranging the non-return valve 13 a between the apparatusinput 11 a and the breathing gas drive 12 a, the non-return valve 13 ais arranged on the suction side of the ventilator 10.

FIG. 12 shows a diagrammatic structure of an alternative embodiment ofthe ventilator 10 according to the invention with the inspiratory airway16 a with the open bypass 17 with the separate apparatus output 15 b.The inspiratory airway 16 a of the ventilator 10 comprises the apparatusinput 11 a and the apparatus output 15 a. The breathing gas drive 12 a,the non-return valve 13 a, a flowmeter 27 as well as the switching valve14 a are arranged between the apparatus input 11 a and the apparatusoutput 15 a, wherein the switching valve 14 a is arranged in the bypass17. The bypass 17 is designed as an open bypass which comprises aseparate apparatus output 15 b as well as at least one flowmeter 27. Theopen bypass 17 branches off from the inspiratory airway 16 a between thenon-return valve 13 a and the apparatus output 15 a, and opens in theseparate apparatus output 15 b. The breathing gas drive 12 a is arrangedbetween the apparatus input 11 a and the non-return valve 13 a. Theswitching valve 14 a can be switched time-controlled, patient-triggeredor based on a flow or volume of the breathing gas detected by theflowmeter 27 arranged in the bypass 17. The flowmeter 27 in the bypass17 is here arranged between the separate apparatus output 15 b and theswitching valve 14 a. Through the switching valve 14 a arranged in theopen bypass 17 it is possible in the event of a blockage of theinspiratory airway 16 a to discharge breathing gas discharged by thepatient through the switching valve 14 a. Through the arrangement of thenon-return valve 13 a between the breathing gas drive 12 a and theapparatus output 15 a, the non-return valve 13 a is arranged on thepressure side of the ventilator 10.

The embodiment illustrated in FIG. 12 further shows that the inspiratoryairway 16 a comprises additionally at least one further valve 26 whichis set up to ensure a supply of oxygen or air or compressed air to theinspiratory airway 16 a. The inspiratory airway 16 a moreover comprisesat least one flowmeter 27 wherein the flowmeter 27 is arranged betweenthe breathing gas drive 12 a and the non-return valve 13 a. The furthervalve 26 can open into the inspiratory airway 16 a between the apparatusinput 11 a and the breathing gas drive 12 a as well as between theflowmeter 27 and the non-return valve 13 a. The further valve 26 is as arule a proportional valve.

With the embodiment shown in FIG. 12 the region (inspiratory unit) ofthe open bypass 17 with the switching valve 14 a, the flowmeter 27 andthe separate apparatus output 15 b, as well as the region of theinspiratory airway 16 a with the non-return valve 13 a and the apparatusoutput 15 a can be removed from the ventilator and autoclaved. Theregion of the inspiratory airway 16 a with the apparatus input 11 a, thebreathing gas drive 12 a and the flowmeter 27 is set up and designed sothat it cannot come into contact with contaminated breathing gas.

The alternative embodiments of the ventilator 10 shown in FIGS. 9 to 11can optionally each comprise a flowmeter which detects a flow or volumeor a pressure of the breathing gas in the airway.

The switching valve 14 a in the alternative embodiments, such as shownin FIGS. 9 to 11, can optionally be switched based on the flow or volumedetected by the flowmeter.

The alternative embodiments shown in FIGS. 9 to 11 can optionally becombined with the embodiments shown in FIGS. 1 to 8. Alternatively, theopen bypass 17 shown in FIGS. 9 to 11 can replace the closed bypass 17in the embodiments shown in FIGS. 1 to 8.

REFERENCE NUMERAL LIST

-   10 Ventilator-   11 a Apparatus input-   11 b Second, separate apparatus input-   12 a Breathing gas drive-   12 b Breathing gas drive-   13 a Non-return valve-   13 b Non-return valve-   14 a Switching valve-   14 b Switching valve-   14 c Switching valve-   14 d Switching valve-   15 a Apparatus output-   15 b Separate apparatus output-   16 a First airway-   16 b Second airway-   16 c Airway, for the expiratory breathing gas flow-   16 d Separate expiratory airway-   17 Bypass-   18 a Flowmeter-   18 b Flowmeter-   18 c Flowmeter-   18 d Flowmeter-   19 Tube system-   20 Patient interface-   21 Expiratory apparatus input-   22 a Expiratory apparatus output-   22 b Expiratory apparatus output-   23 Tube system-   24 First branch-   25 Second branch-   26 Further valves, proportional valves-   27 Further flowmeters

What is claimed is:
 1. A ventilator, wherein the ventilator comprises atleast an apparatus input and an apparatus output and an airway betweenthe apparatus input and the apparatus output, a breathing gas drive, anon-return valve and at least one switching valve being arranged in theairway, the non-return valve preventing a flow of breathing gas in adirection from the apparatus output to the apparatus input and the atleast one switching valve enabling at least temporarily a flow ofbreathing gas in a direction from the apparatus output to the apparatusinput or to a separate apparatus opening.
 2. The ventilator of claim 1,wherein a flowmeter is arranged between the non-return valve and theapparatus output.
 3. The ventilator of claim 1, wherein the at least oneswitching valve is arranged in a bypass around the non-return valve. 4.The ventilator of claim 1, wherein the at least one switching valveforms a bypass around the non-return valve.
 5. The ventilator of claim1, wherein the at least one switching valve is set up to open and/orclose a bypass, the at least one switching valve being configured sothat it can be switched automatically or actively.
 6. The ventilator ofclaim 1, wherein the breathing gas drive is arranged between theapparatus input and the non-return valve and is configured to conveybreathing gas in a direction of the non-return valve and the apparatusoutput.
 7. The ventilator of claim 1, wherein a bypass branches off tothe at least one switching valve between the breathing gas drive and thenon-return valve and opens back again into the airway between thenon-return valve and the apparatus output.
 8. The ventilator of claim 1,wherein the breathing gas drive is arranged between the non-return valveand the apparatus output, and is configured to convey breathing gas in adirection of the apparatus output.
 9. The ventilator of claim 1, whereina bypass branches off to the at least one switching valve between theapparatus input and the non-return valve and opens back again into theairway between the non-return valve and the breathing gas drive.
 10. Theventilator of claim 1, wherein in addition to a bypass a second airwayis formed which comprises a second apparatus input and at least onefurther non-return valve and opens into the first airway before thecommon apparatus output.
 11. The ventilator of claim 1, wherein anadditional airway is formed for an expiratory breathing gas flow andcomprises an expiratory apparatus input and an expiratory apparatusoutput.
 12. The ventilator of claim 11, wherein the additional airwayleads from the expiratory apparatus input to the expiratory apparatusoutput, an additional switching valve and a flowmeter being arranged inthe additional airway.
 13. The ventilator of claim 12, wherein betweenthe expiratory apparatus input and the additional switching valve aseparate expiratory airway comprising a further switching valve and afurther flowmeter leads to a separate apparatus output.
 14. Theventilator of claim 11, wherein a tube system is adapted to theapparatus output and runs with a first branch to a patient interfaceand, before the patient interface, runs with a second branch to theexpiratory apparatus input for expiratory breathing gas.
 15. Theventilator of claim 1, wherein the non-return valve prevents a flow ofbreathing gas in a direction from the apparatus output to the apparatusinput, and the at least one switching valve enables at least temporarilya flow of breathing gas in a direction from the apparatus output to theapparatus input, the at least one switching valve being arranged in abypass around the non-return valve and the bypass branching off to theat least one switching valve between the breathing gas drive and thenon-return valve, and opening back again into the airway between thenon-return valve and the apparatus output.
 16. A ventilator, wherein theventilator comprises an apparatus input and an apparatus output and anairway between the apparatus input and the apparatus output, a breathinggas drive, a non-return valve and a switching valve being arranged inthe airway, and wherein (i) the ventilator comprises a secondinspiratory airway which comprises a separate apparatus input and afurther non-return valve, the second inspiratory airway being set up todraw breathing gas in through the separate apparatus input and convey itin a direction of the apparatus output, or (ii) the switching valve isarranged in a bypass, the bypass being formed as an open bypass whichcomprises a separate apparatus output, the open bypass branching offfrom the inspiratory airway between the non-return valve and theapparatus output and opening in a separate apparatus output, theinspiratory airway comprising at least one further valve and aflowmeter, the flowmeter being arranged between the breathing gas driveand a further non-return valve.
 17. A ventilator, wherein the ventilatorcomprises an apparatus input and an apparatus output and an airwaybetween the apparatus input and the apparatus output, a breathing gasdrive, a non-return valve and a switching valve being arranged in theairway, and wherein the switching valve is arranged in a bypass, thebypass being formed as an open bypass which comprises a separateapparatus output, and the open bypass branching off from the inspiratoryairway between the non-return valve and the apparatus output and openinginto the separate apparatus output.
 18. The ventilator of claim 17,wherein the switching valve is arranged in the bypass and the bypass isformed as an open bypass which comprises a separate apparatus output,the open bypass branching off from the inspiratory airway between thenon-return valve and the apparatus output and opening into the separateapparatus output, the inspiratory airway comprising at least one furthervalve.
 19. The ventilator of claim 17, wherein the switching valve isarranged in the bypass, the bypass forming as an open bypass whichcomprises a separate apparatus output, the open bypass branching offfrom the inspiratory airway between the non-return valve and theapparatus output and opening in the separate apparatus output, and atleast one flowmeter being arranged in the open bypass.
 20. Theventilator of claim 16, wherein the switching valve is arranged in abypass, the bypass being formed as an open bypass which comprises aseparate apparatus output, the open bypass branching off from theinspiratory airway between the non-return valve and the apparatus outputand opening in a separate apparatus output, the inspiratory airwaycomprising at least one further valve and a flowmeter, the flowmeterbeing arranged between the breathing gas drive and a further non-returnvalve.